num = 100
print(id(num))
num = 200
print(id(num))
list = [1,2,3]
print(id(list))
list.append(4)
print(id(list))


def login_front():
    username = "13800000001"
    password = "123456"
    print(f"登录成功, 账号: {username},密码: {password}")


def login_back():
    username = "admin"
    password = "123456"
    print(f"登录成功, 账号: {username},密码: {password}")


login_front()
login_back()


def add_test(num1, num2):
    num1 = 100
    print(num1 + num2)


def sub_test(num1, num2):
    print(num1 - num2)


add_test(10,200)
sub_test(10,200)


num = 10


def demo1():
    num = 100
    print(num)


def demo2():
    global num
    num = 200
    print(num)


def demo3():
    print(num)


demo1()
demo2()
demo3()